Smoothly transition the mute cache across /libertybans restart

A248 · Feb 23, 2024 · 9cb950b · 9cb950b
1 parent b10c847
commit 9cb950b
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Showing 3 changed files with 48 additions and 45 deletions.
diff --git a/...re/src/main/java/space/arim/libertybans/core/selector/cache/AlwaysAvailableMuteCache.java b/...re/src/main/java/space/arim/libertybans/core/selector/cache/AlwaysAvailableMuteCache.java
@@ -28,7 +28,6 @@
 import space.arim.libertybans.api.select.PunishmentSelector;
 import space.arim.libertybans.core.config.Configs;
 import space.arim.libertybans.core.config.InternalFormatter;
-import space.arim.libertybans.core.config.SqlConfig;
 import space.arim.libertybans.core.env.EnvUserResolver;
 import space.arim.libertybans.core.service.Time;
 import space.arim.omnibus.util.concurrent.CentralisedFuture;
@@ -83,15 +82,28 @@ public AlwaysAvailableMuteCache(Configs configs, FactoryOfTheFuture futuresFacto
 	}
 
 	@Override
-	void installCache(Duration expirationTime, SqlConfig.MuteCaching.ExpirationSemantic expirationSemantic) {
-		ConcurrentHashMap<MuteCacheKey, Entry> map = new ConcurrentHashMap<>();
-		Cache cache = new Cache(map, expirationTime);
-		cache.startPurgeTask();
-		this.cache = cache;
+	public void startup() {
+		installCache((expirationTime, expirationSemantic) -> {
+			ConcurrentHashMap<MuteCacheKey, Entry> map = new ConcurrentHashMap<>();
+			Cache cache = new Cache(map, expirationTime);
+			cache.startPurgeTask();
+			this.cache = cache;
+		});
+	}
+
+	@Override
+	public void restart() {
+		installCache((expirationTime, expirationSemantic) -> {
+			Cache oldCache = this.cache;
+			oldCache.stopPurgeTask();
+			Cache newCache = new Cache(oldCache.map, expirationTime);
+			newCache.startPurgeTask();
+			this.cache = newCache;
+		});
 	}
 
 	@Override
-	void uninstallCache() {
+	public void shutdown() {
 		cache.stopPurgeTask();
 	}
 

diff --git a/bans-core/src/main/java/space/arim/libertybans/core/selector/cache/BaseMuteCache.java b/bans-core/src/main/java/space/arim/libertybans/core/selector/cache/BaseMuteCache.java
@@ -31,6 +31,7 @@
 import java.time.Duration;
 import java.util.Optional;
 import java.util.UUID;
+import java.util.function.BiConsumer;
 import java.util.function.Predicate;
 
 abstract class BaseMuteCache implements MuteCache {
@@ -45,8 +46,7 @@ abstract class BaseMuteCache implements MuteCache {
 
 	// Setup
 
-	@Override
-	public final void startup() {
+	void installCache(BiConsumer<Duration, ExpirationSemantic> settingsConsumer) {
 		SqlConfig sqlConfig = configs.getSqlConfig();
 		SqlConfig.MuteCaching muteCaching = sqlConfig.muteCaching();
 
@@ -58,24 +58,9 @@ public final void startup() {
 		} else {
 			expirationSemantic = muteCaching.expirationSemantic();
 		}
-		installCache(expirationTime, expirationSemantic);
+		settingsConsumer.accept(expirationTime, expirationSemantic);
 	}
 
-	@Override
-	public final void restart() {
-		shutdown();
-		startup();
-	}
-
-	@Override
-	public final void shutdown() {
-		uninstallCache();
-	}
-
-	abstract void installCache(Duration expirationTime, ExpirationSemantic expirationSemantic);
-
-	abstract void uninstallCache();
-
 	// Retrieval
 
 	final CentralisedFuture<Optional<Punishment>> queryPunishment(MuteCacheKey key) {

diff --git a/bans-core/src/main/java/space/arim/libertybans/core/selector/cache/OnDemandMuteCache.java b/bans-core/src/main/java/space/arim/libertybans/core/selector/cache/OnDemandMuteCache.java
@@ -31,12 +31,10 @@
 import space.arim.libertybans.api.select.PunishmentSelector;
 import space.arim.libertybans.core.config.Configs;
 import space.arim.libertybans.core.config.InternalFormatter;
-import space.arim.libertybans.core.config.SqlConfig;
 import space.arim.libertybans.core.service.Time;
 import space.arim.omnibus.util.concurrent.CentralisedFuture;
 import space.arim.omnibus.util.concurrent.FactoryOfTheFuture;
 
-import java.time.Duration;
 import java.util.Optional;
 import java.util.UUID;
 import java.util.function.Predicate;
@@ -65,28 +63,36 @@ public OnDemandMuteCache(Configs configs, FactoryOfTheFuture futuresFactory,
 	}
 
 	@Override
-	void installCache(Duration expirationTime, SqlConfig.MuteCaching.ExpirationSemantic expirationSemantic) {
-
-		Caffeine<Object, Object> builder = Caffeine.newBuilder();
-		builder = switch (expirationSemantic) {
-			case EXPIRE_AFTER_ACCESS -> builder.expireAfterAccess(expirationTime);
-			case EXPIRE_AFTER_WRITE -> builder.expireAfterWrite(expirationTime);
-		};
-		cache = builder
-				.scheduler(Scheduler.disabledScheduler())
-				.ticker(time.toCaffeineTicker())
-				.buildAsync((key, executor) -> {
-					return queryPunishment(key).exceptionally((ex) -> {
-						// If we don't catch these exceptions, Caffeine will
-						LoggerFactory.getLogger(OnDemandMuteCache.class)
-								.warn("Exception while computing cached mute", ex);
-						return Optional.empty();
+	public void startup() {
+		installCache((expirationTime, expirationSemantic) -> {
+			Caffeine<Object, Object> builder = Caffeine.newBuilder();
+			builder = switch (expirationSemantic) {
+				case EXPIRE_AFTER_ACCESS -> builder.expireAfterAccess(expirationTime);
+				case EXPIRE_AFTER_WRITE -> builder.expireAfterWrite(expirationTime);
+			};
+			cache = builder
+					.scheduler(Scheduler.disabledScheduler())
+					.ticker(time.toCaffeineTicker())
+					.buildAsync((key, executor) -> {
+						return queryPunishment(key).exceptionally((ex) -> {
+							// If we don't catch these exceptions, Caffeine will
+							LoggerFactory.getLogger(OnDemandMuteCache.class)
+									.warn("Exception while computing cached mute", ex);
+							return Optional.empty();
+						});
 					});
-				});
+		});
+	}
+
+	@Override
+	public void restart() {
+		cache.synchronous().invalidateAll();
 	}
 
 	@Override
-	void uninstallCache() {}
+	public void shutdown() {
+
+	}
 
 	@Override
 	public CentralisedFuture<Optional<Punishment>> getCachedMute(UUID uuid, NetworkAddress address) {